This invention relates to a seat post assembly for attaching a seat to a bicycle and isolating the rider from road shock forces exerted on the bicycle. More particularly, the invention is directed to a seat isolation device providing shock isolation through use of an elastomeric shock absorbing subassembly installed in the seat post. This arrangement isolates the seat and the cyclist from repetitive and random road shocks. Since the entire seat is deflected relative to the bicycle, no rigid or dramatic "bump" is experienced by the rider to cause discomfort.
While the invention is particularly directed to the art of bicycle seat post assemblies, and will be thus described with specific reference thereto, it will be appreciated that the invention may have usefulness in other fields and applications.
Traditional bicycle seats are attached to the bicycle with clamps that attach to two standard rails disposed under the seat. A wide variety of clamps are known, but most are characterized by a rigid connection between the bicycle frame and the seat. Accordingly, with the exception of the tires, there is no isolation between road shock and the seat.
Lack of isolation from road shock is a major difficulty for new cyclists, limiting enjoyment of cycling to their threshold of pain. Experienced riders, while more accustomed to the shock, nonetheless become fatigued more readily by the constant exposure to road shock.
Specialized seats have been developed that isolate shock. However, most cyclists prefer their own seat design. Further, existing seat designs have a rigid, pivoting front end that often is uncomfortable when the rear end of the seat deflects rapidly.
Additionally, shock absorbing seats using spring and shock absorber technology are known. However, these known seats require relatively heavy springs and shafts. The weight of a bicycle is increased with the addition of such springs and shafts. Significantly, in the cycling field, reduction of weight is important. Accordingly, these types of arrangements are not generally desired.
The present invention contemplates a new and improved seat post assembly which resolves the above-referenced difficulties and others.